Because of U.S. Federal specifications of bumper heights (i.e., sprung weight) of land vehicles, the need for a universal height gauge has been created. In the past this height reference has been confined generally to its effect on the wheel camber attitude.
Various car manufacturers specify various points of reference to achieve the desired results. Some specify measurement of upper and lower knee action parts, others specify frame to floor measurement, while others specify torsion bar to floor measurement. To control front bumper heights and disregard rear bumper heights is inadequate in that a majority of car accidents involve the front of one, and the rear of another car. Accordingly, it is anticipated that both front and rear bumper heights will be specified in the future.
While the various car factories can specify a given method or means to their own dealers, this will not suffice for the general service station or repair garage. The need for a comprehensive gauge seems obvious. Such a unit must resolve not only variations in heights, from various points on the various vehicles, but also while the vehicle is in various positions as follows: (1) Torsion bars to floor; (2) Torsion bars to drive on lift; (3) Torsion bars to rack aligner turntables; (4) Side frame rail to floor; (5) Rear frame rails to floor; (6) Frame to lower control arm.